Re: [PATCH 0/2] Refactor ioreq server for better performance.

["Yu, Zhang" <yu.c.zhang@linux.intel.com>]

Oh, I forgot the version number and change history.
This patchset should be version 2.

The change history should be:
1> Split the original patch into 2;
2> Take Paul Durrant’s comments:
     a> Add a name member in the struct rb_rangeset, and use the ‘q’
debug key to dump the ranges in ioreq server;
     b> Keep original routine names for hvm ioreq server;
     c>. Commit message changes – mention that a future patch to change
the maximum ranges inside ioreq server;

Sorry, my fault. Could I add this change history in next version,
or should I resend the version 2? :)

Thanks
Yu

On 7/2/2015 8:31 PM, Yu Zhang wrote:
> XenGT leverages ioreq server to track and forward the accesses to
> GPU I/O resources, e.g. the PPGTT(per-process graphic translation
> tables). Currently, ioreq server uses rangeset to track the BDF/
> PIO/MMIO ranges to be emulated. To select an ioreq server, the
> rangeset is searched to see if the I/O range is recorded. However,
> traversing the link list inside rangeset could be time consuming
> when number of ranges is too high. On HSW platform, number of PPGTTs
> for each vGPU could be several hundred. On BDW, this value could
> be several thousand.
>
> To accommodate more ranges, limitation of the number of ranges in an
> ioreq server, MAX_NR_IO_RANGES is changed - future patches will be
> provided to tune this with other approaches. And to increase the ioreq
> server performance, a new data structure, rb_rangeset, is introduced.
>
> Yu Zhang (2):
>    Resize the MAX_NR_IO_RANGES for ioreq server
>    Add new data structure to track ranges.
>
>   xen/arch/x86/domain.c            |   3 +
>   xen/arch/x86/hvm/hvm.c           |  56 ++++++--
>   xen/common/Makefile              |   1 +
>   xen/common/rb_rangeset.c         | 281 +++++++++++++++++++++++++++++++++++++++
>   xen/include/asm-x86/hvm/domain.h |   4 +-
>   xen/include/asm-x86/hvm/hvm.h    |   1 +
>   xen/include/xen/rb_rangeset.h    |  49 +++++++
>   7 files changed, 379 insertions(+), 16 deletions(-)
>   create mode 100644 xen/common/rb_rangeset.c
>   create mode 100644 xen/include/xen/rb_rangeset.h
>